Induction heat-treating apparatus



Nov. 26,- 1946. H. E, SOMES 2,411,698

INDUCTION HEAT TREATING APPARATUS Filed May 10, 1941 10 Sheets-Sheet 1 5 H I WI? I W!" gut All MT v INVENTOR Howard B Somes ATTORNEY Nov. 26, 1946. H E. soMEs I INDUCTION HEAT TREATING APPARATUS Filed May 10, 1941 '1o Sheetsv-Sheet 2 INVENTOR Howard E-Somes ATTORNEY H. E. SOMES INDUCTION HEAT TREATTNG APPARATUS Filed May 10, 1941 10 Sheets-Sheet 3 crf j- L cart-H n :1I|IB.

INVENTOR Howard E. Somes ATTORNEY Nov. 26, 1946. H. E. SOMES INDUCTION HEAT TREATING APPARATUS Filed May 10, 1941 10 Sheets-Sheet 5 .2 kn lll l xl hlllllll "llllllll; I g 1 11,111

IN VENTOR Howard BSofnes BY F v ATTORNEY- H. E. SOMES' INDUCTION HEAT TREATING APPARATUS Nov. 26, 1946.

Filed May 10, 1941 lO-Sheets-Sheet 7 I FvHHIIPPFIIL Nov. 26, 1946.

H. E. SOMES INDUCTION HEAT TREATING APPARATUS Filed May 10, 1941 10 Sheets-Sheet 9 I 196 INVENTOR HawardBSomes ATTORNEY Patented Nov. 26,

INDUCTION HEAT-TREATING APPARATUS Howard E. Somes, Detroit, Mich assig'nor, by. mesne assignments, to The Budd Company,

vania Philadelphia, Pa., a corporation of Pennsyl- I Application May 10, 1941, Serial No. 392,867

10 Claims. 1

This invention relates to heat treating apparatus and more particularly to heat treating apparatus adapted to heat treattthe internal surface of tubular or cylindrical members.

i The apparatus is especially adapted to hold a cylindrical hollow member and rotate the same while at the same time progressively move the hollow member relative to a heating head and a quench head to heat treat the same from one end to the other. The apparatus is adapted to accurately hold the hollow member in place during the heat treating operation and to move the same longitudinally relative to the heating and quench heads at an accurately controlled rate of speed and to perform the operations rapidly,. automatically and safely. The invention constiing in section to better illustrate certain detailsthere'of Figure 4 is a transverse section taken substan-. v

tially on line 4-4 of Figure 3; re 5 is a sectional vlew'taken on line 5-5 of Fi ure 4;

Fi ure 6 is a transverse section taken sub- 4 stantially onllne 6-6 of Figure 3; I

tutes an improvement over the app'aratus dis- 1 closed in Patent No. 2,281,297 and Patent No.

2,281,331, both dated April 28,. 1942.

An object of the invention is to provide heat treating apparatus having automatic control over the operation and relative movement of the various parts and in which time control is coordinated with the relative movement of these-parts.

Another object is to ,provide' automatic control for apparatus of the type set forth in which a high degree of safety against possible damage and trouble is assured.

Another object 'is to provide'in an heat treating apparatus means whereby operation of the same cannot proceed until the workpiece to be heat treated is in proper position for heat treatment.

Another object is to provide in an induction heat treating apparatus having a fluid cooled inductor, means whereby electric current cannot be-delivered to the inductor until a predetermined fiow of cooling fluid through the inductor is established.

The above and other novel features of the invention will appear more fully hereinafter from the following detailed description when taken in conjunction with the accompanying drawings. It is to be expressly understood, how-' induction Figure 7 is an enlarged vertical section take through the switching transformer to show the general arrangement of the parts thereof;

Figure 8 is a horizontal section taken in theregion of the upper'cross head of the work carriage to show the capacitors and the arrangement for conducting cooling fluid to the heat head arbor;

Figure 9 is a section taken substantially on 1 line 9-9 of Figure 8 Figure 10 is a vertical section taken substantially on line Ill-l0 of Figure 3 to show the structural details of the heat and quench heads;

Figure 11 is an enlarged view in elevation of 1 a portion of the right side of the apparatus i1- lustrated in Figure 3;

Figure 12 is a side elevation of a control featuretroller operated switches;

the front and one side of the apparatus and il r lustrating its general arrangement;

Figure 2 is a rear elevation of the apparatus;- Figure 3 is an enlarged front view of the central portion of the apparatus, parts thereof be- Figure 14 is a diagrammatic illustration of the hydraulic control system employed in conjunc tion with the apparatus; I V

Figure 15 is a diagrammatic illustration of the cooling and quenching apparatus and of the fluid pressure controls, therefor; and

Figure 16 illustrates a wiring diagram through which automatic operation of the apparatus is achieved.

Referring-to the drawings, in which like numerals refer to like parts throughout the several views, particularly Figure 1, there'is generally illustrated a heat treating apparatus including a rigid upright frame 40 of hollow box section having a vertical recess iii in the front face thereof which, in efiect, provides spaced vertical side columns 82. Secured to the columns t2 by upper and lower end clamping members 63 is a pair of spaced upright parallel carriage guide rods 46 upon which a reciprocable work upport-' ing carriage 45 is mounted The carriage includes sleeves. 0r cylinders 66, surrounding the tion engine cylinder, is supported, in proper position for the heat treating operations to be performed thereon, between lower and upper chuck fixtures 48 and 50 (to be later described) respectively carried by the chuck supports 41 and 48.

Supported on the upper ends of the guide rods 44 by a cross member-| is a switching transformer, generally designated 52, and depending from the transformer 52 is an electrical conductor arbor 53 having an induction heating head 54 (see Figure 3) at its lower end.

A quenching apparatus, generally designated 55 is supported in axial alignment/with the arbor 53 by a bracket 55 provided at the lower portion of the frame between the guide rods 84, the nozzle 51 (see Figure 3) of which is-w'ithin the chuck fixture 48 and the elevating and retracting mechanism 58 therefor is disposed below the bracket It will be observed that the rigid frame 40, the bracket 56, the guide rods 44, and the cylinders 45 bridgedby the members 41, 48 and 58 are suflicient to provide a rigid supporting means for maintaining the arbor 53, the workpiece W and quenching apparatus 55 in accurate axial alignment with one another for precision work.

Referring to Figure 3 wherein the central portion of the apparatus is illustrated in enlarged section, it will be observed that the guide rods 44 are each comprised of an upper member 58 and a lower tubular member 5! threadedly joined together by an intermediate piston member 52.

Each of the carriage sleeves 45 constitutes 8. cylinder adapted to cooperate with a piston member 52 and having its ends slidably sealed on the guide rod 44 by packing glands 53. Each sleeve thus forms a double acting cylinder. Fluid under pressure is admitted and discharged. through ports 54 and 65 above and'below the piston member 62 into the cylinder to effect reciprocation of the carriage 45, it being understood that admissionof fiuid above the-piston members 82 will elevate the carriage and admission of fluid below the piston members I32 will lower the carriage.

The main lower fixture support 41 is bored at its ends to receive the sleeves 48 and is secured to the sleeves 46 by split annular keys 54 arranged partly in annular grooves in the sleeves and between the lower ends of the sleeve receiving bores 65 and the retaining collars 86. The support 41 is provided with a central vertical opening within which antifriction bearings 51 and 68 are supported to rotatably support an annular spindle 58 to which is secured an annular work sup rting member 18 of the lower fixture 48.

The member 18 supports an annular chuck 1| of the resilient finger type such as is shown in my Patent No. 2,288,037, issued June 80, 1942, the chuck being adapted to grip the lower end of the workpiece W.

The lower end of the member 48 is provided with an annular housing 1Ia which surrounds.

gear 18 secured to the spindle 58, The housing 1 Ia supports motor 12, the shaft of which carries a pinion 13a meshed with gear 13 for rotating the lower chuck I I.

In order to support a tubular article of considerable length such as the workpiece W in accurate alignment with the heating head 54' and quenching head 51 the upper fixture 58 is provided, the upper support 58 of which is secured to the sleeves by split clamps 5811 through screws 58b. In practice, in order to accommodate workpieces of different lengths, the upper support 58 upon loosening of the screws 58b may be slid along the sleeves 48 to the desired position. The

support is open between the sleeves and receives and supports at substantially uniformly spaced circumferential points three vertical cylinders 14 having pistons 15 reciprocable therein from which depends rods 15. These rods support an,

annular housing member 11 forming a part of the upper fixture 58 and which through spaced antifriction bearings 18 and 18 supports an annular member 80 and an external sleeve 8I connected together through plate 82. The annular member 88 through plate 83 supports an upper chuck 84 which preferably is of the same type as the lower chuck 1|. The sleeve BI is provided with'gear teeth 85 which mesh with a pinion mounted on the shaft 85 of a motor 81 carried by the supporting housing 11. The gear and pinion being identical in gear ratio with 'the gear 13 and pinion 18a and otherwise, as are the motors 12 and 81,to effect rotation of the two chucks at identically the same speed.

The cylinders 14 are connected together at bottom and top by manifolds 88 and 88, the manifolds 88 and 88 connecting the lower and upper ends of the cylinders respectively as indicated at 80 and 8|. The manifolds are each provided with a connection 82 secured to the side of the support I 58 and from thence to the source of operating pressure through flexible conduits 83 and 84.

The apparatus as illustrated in Figures 1 and 3 shows the heating head 54 and the quenching head 51 in operative position for the start of the heat treating operation, the carriage being in elevated position. To commence the heat treatment of the internal surface of the workpiece W it is merely necessary to energize the heating head 54, supply quenching fluid to the quench head 51 and move the carriage downwardly to effect relative axial movement of the two heads on the one hand and the workpiece on the other hand.

Since in order to place the workpiece in the position shown, the heat head and the quench head 51 must be separable from one another, provision is made for elevating the quench head into the position shown and retracting the same to a lower position through the elevating and retracting apparatus 58 which includes a fluid pressure cylinder 95 and piston to which latter the quench head supporting tube 81 is connected. The cylinder 85 is supported beneath the bracket 55 through the upper cylinder head 88, the latter having a flange 88 bolted to the under side of the bracket 55. The cylinder 85 is threaded into the-upper cylinder head as at I08 and telescoped with a skirt extension I8I thereof. The lower end of the cylinder 85 is closed by the lower cylinder head I82 and a port I03 for supplying fluid under-pressure to the lower end of the cylinder is provided therein.

In order to provide for the supply of quenching fluid to the heating head 51, the piston is so constructed and arranged as to act as a slide valve to the end that the quench head whenin in the wall of and at the upper end of cylinder pressure.

' 66, the portsc onnecting with an internal annular nected to-the piston through a split key I03 and 1 threaded lock ring I09 and is aligned with a central axial bore IIO extending through the piston and which bore is. capped at its lower end by the flanged combined packing retaining nut and plug 7 II I. The annulargroove I04 is connected to the central port IIO through radial .ports II2. The

upper head 66 is additionally provided with a fluid passage H3 at the end of cylinder 95 for the admission of fluid to the upper end thereof for acting on the upper side of the piston for lowering the quenching apparatus under fluid In order to provide for the drainage of quenche ing fluid supplied .within the workpiece W from the quench head 51, the spindle-60 of the lower rotatable support is larger in;di'am'eter than the I port member 'II is provided with a'central aperture II4 and aniupstanding sleeve II5, the sleeve having at its upper end a fluid-tight washer II6 engaged with the lower end of the spindle 69. A

chamber I" through which the quench tube 91 passes is provided'with a} water-tight packing II6 atits lowerend and is secured to the underside of the bottom -of the motprsupport and gear casing II and in alignment-J with the aperture ingdownwardly through spindle 69 may be .car-

ried away therethrough.

The switching transformer 52- as shown in Figure 7,,whi'ch is more clearly shown and described and is claimed in my Patent No.

2,348,082, the application for which was a division of this application, includes, in general, a hous-T ing IZII having a bottom supporting plate I2I which supports an annular member I22 which in turn supports an annular secondary element, the secondary element embodying a support I23,

' a surrounding magnetic core I26 and a water cooled secondary winding I25, One terminal of the winding I25 is electrically connected to the support I23 and theother to an annular ring I26 within-and insulated from the support I23., Suitable cooling water conduits I27 and I 28 are connected through the support I23 and ring I25 respectively to the winding terminals for, conducting cooling. water through the winding.

The primary element of the transformer is annular in form and embodies an annular shell.

I29 which houses the magnetic core I 30 and water cooled primary winding I3I, the terminals I32 and I33 thereof extending outwardly through the shell I29 and an elongated slot I34 in the casing no and are connected to terminals I35 and 136 respectively which lead to the source of power (not shown). Suitable flexible water co'hducting conduits I37 and I33 are connected to the terminals I35 and I36. The primary winding supporting shell I29 is slidable inthe casing I 20 from the coupled position shown in Figure '7 to an uncoupled position adjacent the'plate I2I in surrounding relation. with respect to a magnetic element In by the annular member m which is connected to an actuating red I. The rod I4| The mechanism for actuating the primary element may be of anysuitable fluid pressure operated type.

The arbor Sit-embodies concentric inner and outer-conductors I43 and vI44'resp'ectively insulated from each other by an insulating sleeve I45, the inner conductor I43 being electrically connected with the ring I26 through connector I46 and the outer conductor being connected with 15 the support I23 through the annular member I22,

the latter being insulated from member I22.

i The conductors I43 and I44 at their lower ends (see Figure 10) are internally and externally threaded respectively to receive heating head adaptor elements I41 and I48. The adaptor element I" is hollow at its opposite ends and has an intemal' web I 49 provided with an axial threaded opening and surrounding passages I50, The element In is threaded into the inner conductor I43 and is insulated as at II from the outer conductor I44. Adaptor element I46 is of an annular formation threaded to the outer conductor I44 and having downwardly extending contactor fingers I52.

, The heating head 51, which forms the subject matter of and is described and claimed in my copending application Serial No. 336,129, filed May 20, 1940, comprises in general, an annular support I53 supporting a surrounding core I54 which in turn supports a tubular heating coil I55, and an internal hollow sleeve I56 insulated by a non-conductingsleeve I51 from the support I53. One end of the coil I55 is insulated from and extends through the support I53 and is electrically connected to the sleeve I56, the connection being hollow to provide communication between the coil passageway I 55 and the bore I59 of the sleeve I55. The opposite nd of the coil I55 is connected tothe support I53 which has a passage I60 through the wall thereof communicating with the coil passageway I58.

The sleeve I56 fits snugly within the end of the adaptor III? in electrical contact therewith and the support I53 extends within the contactor fingers I52 in electrical contact therewith, the

head being secured to the adaptor element It? by a bolt lei extending through the sleeve I56 in spaced. relation except for its head portion I62, and threaded within the web I49 of the adaptorv elementas indicated at I53. The lower end of the annular support is provided with a valve means comprising an upper valve part I66 threaded into the lower end of support, a lower annular valve part I 65 also threaded into the same end of the support but spaced from the part I64 to provide communication between the support passage I60 and the space I10 between the. parts I64 and I65, and a ball member I56 normally closing the axial opening It] in the end 85 I58 of the lower valve part I65. The end of the party I65 is conical as indicated at I69.

The inner conductor I4? of the arbor 53 is tubular to provide a passage III for conducting cooling fluid through the inner adaptor passages vided within the frame near the top thereof..

Connections to these capacitors are provided through a pair of concentric tubular conductors I18 and I14 separated by an insulating sleeve I18, the conductor I13being threaded into the arbor conductor I08 and the conductor I10 being elec-" trically' connected to the outer-arbor conductor by a suitable connedtbr I18. Suitable con- 7 nections I11 and I18 extend from the other ends of the conductor I10 and I10, respectively, to the capacitors I12. Connected with the inner conductor I13 is a conduit I18 for conducting cooling fluid through the conductor I18 to the inner con-.- ductor of the arbor. This conduit connects through a manual shut off valve I80 with conduit I 88 which receives cooling fluid under pressure from a motor driven pump I82 (see Figure Associated with the conduit I86 is a flow switch I88, the function of which will be later described. 7

The quench head 80 (see Figure 10) is comprised of theenlarged upper end 888 of the tube 81 which supports annular inner and outer parts 313i and 382, parts 88I and 882 being axially spaced to provide a circumferential discharge passage 803 and having a supply chamber 300 therebetween which receives quenching fluid from the bore of the tube 81 through a passage 888 and circumferential recess 808 in the enlarged upper end and ports 381 in the wall of part 88L The upper end 300 is provided with an axial pocket 808 and an upstanding pin 808. The upper end is also provided withconical wall 8I0 which when the heads are brought together engages the conical wall I88 of the heat head valve part I85 in fluid tight sealed relation. In this position of the heat head and quench head, the

' pin 308 raises the ball I88 from its seat to permit the flow of cooling fluid into the pocket 888.:

The cooling fluid flows from the pocket 308 through a downwardly extending passage 8 formed through the enlarged end 380. Quenching water, as well as water under pressure for lowering the quench head 81, is taken from the water main I84 (see Figure 15) and after passing through a, filter I85 and the same raised in pressure by a booster pump I88. is delivered through pipe I01 to the cylinder 88. Water from thesame supply and under the control of a valve I88 is delivered through pipe M8 to the cylinder 88 above the piston 88 for loweringv the quench head 51.

Cooling water is delivered from the same source through conduit I80 having a flow switch "I therein for cooling the capacitors I12.

Air from a source of air pressure (not shown) is delivered through conduit I81 having an air filter I88 therein and thence through a control valve I88 to the conduit I08 for delivery to the cylinder 8| into the space below the piston 88 to raise the quench head'81.

Air from conduit I81 is also supplied to conduits I92 and I83 for controlled deliver through valves I80 and I88 respectively to the actuating mechanism I42 (see Figure 1) for eflecting switching movement of the transformer primary winding -I3I.

Circulation of cooling fluid through the transformer windings is effected through the medium of a circulating pump I88 which delivers the cooling medium from a source (not shown) to the primary and secondary conduits I38 and I28 respectively. The cooling fluid returning through primary and secondary conduits I31 and I21 respectively first flows through a radiator I81 and -8 thence through conduit I88 back to the pump v I88. Suitable flow switches I88 and 280 are associated with the return conduits I81 and I21 respectively for a purpose to be later described.

L With reference to the means for effecting reciprocation of the carriage cylinders 08, the fluid pressure actuating system therefor is diagrammaticallyshown in Figure 14. A dual supply of oil or other fluid under pressure is provided by pumps 20I and 202 which are driven by a, motor 208, the pumps delivering the actuating fluid from a sump 280. i

The pump 202 delivers fluid under pressure through pipe 288 to a magnetically actuated control valve 288, there being a pressure relief valve 201 in pipe 208 for relieving line pressure when control valve 288 is in the center position indicated. Raising oi the upper chuck fixture 88 is eflected by energizing valvesolenoid 208 Of the control valve 208 .to shift the valve 208 so as to deliver fluid to conduit 208 through a check valve 2I0 and thence through conduit 88 to the manifold 88 in the upper cross support 88 (see Figure 3) and thence to the cylinders 14. lowering of the chuck is prevented by check valve 2I8 which is spring biased and prevents return flow of fluid except under positive pressure. To: lower the chuck fl'xture 88, valve solenoid 208'. is deener-,

gized and-valve solenoid 2I2 of valvel208 is energized to supply fluid through conduit 88 and thence to manifold 88 (see Figure 3) which forces the pistons in cylinders 10 downwardly, forcing the dischargeoi fluid through conduit 83 and overcomin g the heat of the. check valve 2I0, thereby permitting drainage of the fluid to the sump 200through valve 288 and pipe 2.

Upward and downward movement of the carriage is effected through the application of fluid under pressure derived from pump 28I which is so adjusted as to deliver fluid under specific pressure whereby to provide for accurate control.

Upward movement of the carriage is effected by energizing valve solenoid 2 I8 of control valve 2I8 and valve solenoid 2 I 1 of control valve 2I8 whereby fluid under pressure will pass from pump 20I through conduit 2I 8, control valve 2I8 and conduit 220 to control valve 2I8. From valve 2I8, fluid under pressure flows through a biased check valve 22I by way of conduit 222, to pipes 228 which extend within guide rod portions 8| (see Figure 3) and admit fluid into the cylinders 48 above the pistons 82, the fluid under pressure thus'elevating the carriage to the position shown in Figure 3, this being the position for the start of theheat treating position. During the upward movement,'the fluid in the cylinders at the 'under sides of the pistons 82 is discharged through passages 88 (see Figure 3) and thence through pipes 220, also within the guide rod portions 8I (see Figure 3), pipe 228, and through control valve 2 I8 to the sump 280 by way of drain pipe 228.

trol valve 2I8 (this, Of course after deenergization of solenoid 2I8) so as to deliver fluid under pecific pressure from the pump 20I through pipes 228 and 220 to cylinders below the pistons 82 thereby lowering the carriage. Lowering moveis provided to prevent ment is restricted". however, by the discharge of fluid from the upper ends of thecylinders 43 and through pipes 223 and 222 and'the valve 2l8, the

solenoid 2" of which is deenergized during .this movement, by a metering valve 223, the valve 223,

discharging the fluid through pipe 223 for return to the sump 204. The metering valve 223 is so adjusted as to fix the rate at which fluid may discharge to the sump to thereby positively control the downward carriage movement so long as valve "solenoid 2 I1 is deenergized and the metering valve Since it is essential for safe operation of the machine that the lower and uppe chucks II and i 34, respectively, be precisely in correct engagement with the workpiece W and that the workpiece be of the proper length, a limit switch L;-l operation of the apparatus in the event the chucks do not accurately position themselveswith respect to each other for a given workpiece. For this purpose, as will appear in P Figure 1, the upper chuck fixture 50 is provided with a bracket 230 (see also Figure 12) securedto the housing 11 to which bracket an upwardly. extending rod 23! is secured, the rod at being 30 arranged'to reciprocate, with the upward and downward-chuck opening and closing movement of the upper chuck fixture, through a guide bracket 232 secured to the upper support 53. The up-- per end of the rod 23l is provided with an adjustable cam 233 adapted to engage a slidable plunger 234 which actuates the contacts of the limit switch Ll, the-limit switch being fixed to the bracket 232. Thus, the upper chuck 34 must be in a predetermined lower workpiece engaging position before the plunger the. limit switch Lf-l can be engaged by the cam 233, Figure 12 showing this engaged position. The operation of the limit switch L l inv the system will be presently described. g

The uppermost cylinder bridging member 48 (see Figures 1 and 9). is provided with a depending sleeve 235 slidable on and surrounding. the heat head arbor 53 which during downward heat treating movement of the carriage serves to prevent any possible lateral deflection of the arbor and heat head relative to the workpiece whereby to insure accurate axial .ali'gnmentduring the heat treating operation.

In order to automatically control the carriage movement and other functions of the apparatus, including the heating and quenching operations, which depend upon the movement of the carriage, cam carrying bars 236 having adjustable cams, generally designated 231, thereon, are secured to the carriage cylinders 46 (see Figures 1, 3 and 11) These cams are adapted to open and close various limit switches L-2 to L-9, mounted on the columns 42 of the frame 40, during upward and downward movement of the carriage. The op eration and function of these limit switches will be presently described.

Associated with the front of the machine for convenient access are several manual control switches, viz, a master safety on and off'switch 233, a safety heat-off switch 233, and a master starting switch 240.

The automatic control of the operation of the machine, after initial starting, is mainly by a sequence controller 24! shown in dotted outline 'in tion, Serial No. 450,034, filed July 7, 1942, may be drum type for actuating a number of switches A to L, respectively, in predetermined of the sequence (see Figure 13 andthe wiring diagram or Figure 16). I To best understand the automatic operation or the apparatus, reference may be had to the diagram of Figure 16. Before describing the operation, function of the various limit switcheswhich with 'the sequence controller provide .a space-time control,

Limit switch L-i operates to close a circuit only when the top and bottom chucks "are in proper spaced arrangement and engagement with 20 the workpiece W, which circuit must be closed before further operation suit. 7

{l Limit switch L-2 is a closed circuit switch which is opened by the carriage when elevated to a desired position or upper limit.

is closed at the upper I particular point in the initial downward travel of the carriage, closure thereof being required before the high frequency power can be applied to the transformer and coil of the heating head.

Limit switch L-4, normally open, is closed upon the carriagemoving toward or approach,-

' ing an elevated position and after thesequence controller con excitation in the high frequency generator in anticipation of heat treatment.

Limit switch L-5 is closed at the upper limit .or at a particular point in the initial downward travel of the carriage, closure thereof being required before the switching transformer can operate to coupled position.

Limit switch L-B, normally closed, is adapted to be opened upon the-carriage arriving at a lower position at the end of the heat treating operation to terminate the heating.

Limit switch L-'|, normally closed, ,is opened upon the carriage arriving at the end of its heat treating movement, and opens the field excitation tic-circuit of the generator.

' Limit switch L-3, normally closed. terminates the constantspeed downward movement of the carriage.'

Limit switch L-9, normally closed, is operative to terminate the final downward movement of the carriage.

The sequence controller switches A to L are all open circuit switches and operate to close circuits at predetermined times, as now will be described.

0 Referring to Figure 16, current is delivered through'a three phase line.245, 243 and 241, and to commence operation, the switch 246 for the sequence controller motor 242 is closed which I establishes a circuit 243 with the phase 245, 241. 66 Included in this circuit is a solenoid 249 which whenci'rcuit248 is energized closes switches 243a and 24% in circuit 250 which includes the sequence controller motor 242, thus starting the sequence controller 2 in operation. Energization 7 of solenoid 249 also closes a switch 2430 in a circuit 25l to condition this circuit for operation which includes a solenoid 252 in series with the normally open master starting switch 240 and the normally closed master safety switches 233.

Included alsoin this circuiti's a manually closable it will be necessary. to first consider the I of the machine can re- Limit switch L--3 is a pre-set safety switch and limit or position or at a tacts F are closed to establish field I 11 switch 253 which isclosed normally. but is shown as open in Figure 16. Bridging the master switch 245 is a locking circuit which includes a normally open switch 252a actuatable by solenoid 252.

The circuit 25I vconstitutes a master starting circuit which is efiective for energization on the closure of solenoid switch 2490. Further circuits are divided into two stages, viz., a first stage 255 and a second stage 254. Upon manual closure 'of the master control switch 245 the circuit 25I is energized which through energization of solenoid 252 closes switch 252a to lock out the master control switch 245 and closes switches 25% and 252c to connect the first stage 255 with phase wires 245, 241.

With additional reference now to Figure 13,

which is an operation diagram the heavy lines A to L corresponding to the period of operation of the various elements by the sequence controller switches A to L, and the horizontal lines A to L. dotted and heavy corresponding to time intervals 0 to 100, after energization of the first stage 255. and upon'closure ofsequence controller switch K, relay solenoid 255 is energized which closes relay switch 255a. If flow switches I99, 255 and I9I (see Figure 15) are closed, in which case a lamp 255 (on the front of the machine) will be lit, thus indicating a normal flow of cooling fluid to the transformer primary winding, transformer secondary winding and the capacitors, a circuit 251 will be completed through relay switch 255a which through a signal lamp 255, on the front of the machine will indicate an interval during which loading of the workpiece into the carriage may take place. This interval is indicated by the heavy line'K of Figure 13.

Upon loading the lower chuck with a workpiece W, the upper fixture and chuck may be caused to close upon the closure of sequence controller switch 0, provided that the switch 255 is closed for automatic operation, a circuit being completed between the extension 2411: 01

line 241 and line 245 through switch 255a, se-

quence controller switch 0 and valve operating solenoid 2I2, the latter operating to energize valve 255 (seeFigure 14) to deliver fluid under pressure to the upper ends' of cylinders "to lower the chuck into engagement with the workpiece W. Switch 255a is a i le switch for use in obtaining slight movement for adjustment oi the upper fixture. Closure oi the limit switch L-I is effected only when theupper chuck is in proper position.

Limit switch L-I, relay switch 255b, sequence controller switch A are arranged to complete a circuit 259 through relaysolenoid 255 and flow switches I 99, 255 and I9I to close relay switch 255a in parallel with relay switch 255b'and to also close relay switch 25% which closes circuit 25I, circuit 25I including a relay solenoid 252.

Previously upon energization of the flrst'stage 255, the cooling water supply pump I95 and the oil pressure supply pump motor 255 having been set in operation by the relay switch solenoid 255 which is in series with the normally closed switch 254, which is a switch that must be closed first for automatic operation.

Energization or the second stage 254 isef- I adapted through clutch 255 to open switch 255d which stops the cooling water pump I52 and oil pump motor 555. As a result flow switches I 59,

'ating of the same under the conditions stated.

With the energizing of the second stage 254,

.and through the subsequent closing or the sequence controller D the valve solenoids trend 7 2" of the carriage control are energized, the relay switch 255c in branch circuit 259 with solenoid 2I5, having been closed as a result of closure of sequence controller switch K and the energizing oi relay solenoid 255. As a result, the carriage is caused to elevate until limit switch L-2 is opened by a cam on one'oi the cam bars, which thus deenergizes the control valve solenoids2l5 and 2H. During this upward movement or the carriage the sequence controller switch F closes, and limit switch L-4 also closes near the end of this stroke which energizes relay solenoid 215 to in, turn close switch 215a, looking out limit switch L-4, and closing the switch in the generator field circuit 21I. The high frequency generator is thereby prepared for power generation. It is to be noted at this point that one 01' the important features of the present invention is that if the limit switch L-I failed to close during loading of the chucks with the workpiece, due to improper positioning of the workpiece or a workpiece of improper lengthwhich prevented lowering of the upper chuck to the exact predetermined position, relay solenoid 255 remains deenergized with the result that re-" proper loading or loading with an improper workpiece.

When the carriage reaches its upper limit, se

quence controller switch E closes to energize relay solenoids 21I and 212 to close motor switches 21 Ia, 21Ib and 21Ic for the chuck rotating motor 12 and motorswitches 212a, 2121) and 212c for the chuck rotating motor 51, thus causing simultaneous rotation of the chucks and workpiece W. Also at this time. valve solenoid I59 is energized causing compressed air to raise the quench head 51 into engagement with the heating head 54. At the same time, the booster pump I52 is set in operation through energization oi solenoid 215.

. When the quench head 51 engages the heat head 54 the pin 559 raises the ball valve I55 01 the heat head (see Figure 10) from its seat to openthe cooling fluid passage through the quench head pocket 555 and passage 5| I. Upon the booster pump I52 buildingup a predetermined pressure necessary for adequate cooling, the flow switch I55 closes. Sequence controller switch G then closes circuit 214 to cause energization of relay solenoid 215 to set the quench fluid booster pump I inoperation to suppl quenching water to the quench head 51. At approximately this same time, sequence conthe speed being controlled by the adjustment oi the metering valve 225 (see Figure 14). As the f carriage leaves orpasses the limit switch L-5 .in its initial downward movement, switch 255a, which was previously-closed withthe relay solenoid 255, acts'through closed limit switch L-5 13 to energize relay solenoid 219 to close switch 219a,

locking out limit switch L-3 which subsequently ure 1) moves the transformer primary l9! into coupled relation with the primary secondary I whereby to supply current to the heating head 94.

If the booster pump J82 fails to supply cooling fluid to the heat head coil under suflicient flow conditions for adequate "coil cooling, then flow I switch I 88 remains open and prevents energizetion of relay solenoid 219 and as a result the switching transformer cannotbe actuated to supply current to the heat head coil.

Should emergency conditions require that the power be cut off, the manually operable heatofi switches 239 may be actuated to open the circult to the relay solenoid 219, thereby opening the circuit to the relay solenoid RI and transformer solenoid 282.

This all takes place at the early stage ot-the cycle as seen from the .operating cycle of Figure 13, and is substantially the condition which prevails whenthe parts are in the position shown in Figure 3. a

The carriage carries the workpiece W downwardly at a rate of, for example, one to two inches per second, depending upon the desired rate of heating ofthe bore of the workpiece to recalescence and quenching to produce the desired internal layer of metal. I

As the carriage reaches the end of its controlled downward travel, which corresponds to the heating period (see J of Figure 13), limitswitch L8 opens the circuit to valve solenoid 221, thereby causing e carriage to dwell, and at substantially the same time sequence controller switch I opens, assuring the dwell at this time Atsubstantially the same time limit switch L8 opens the circuit through relay solenoid 219 and as a result deenergize valve solenoid 221 to cause the car riage to come to rest in its lowermost position. Sequence controller switches H and D open at about this time.

Sequence controller switch iii. opens Just prior to the opening of switches H and D thus lowering the quench head by cutting off the air pressure, permitting water pressure to efiect this retraction. Also, at the same time the high pressure cooling water to the heat head is cutoff.

.When the lowermost position of the carriage is reached sequence controller switch B closes to energize valve solenoid 208 and raise the upper chucking fixture to disengage the workpiece W and thereby permit removal of the workpiece.

Through the provision of log switches 283 and 284, upward or downward movement of the carriage, at will, is provided for, the same. deriving I their energy for operating valve solenoids 221, 2|! and M1 from the extension leads 2": and 241:. Similarly there are provided manual switches 29! and 299 bridging sequence controller switches C and B, and connected in circuit with extension leads 2: and 241:: and valve solenoids 2l2 and 208 to open and close the upp r chuck fixture at will.

' The general operation or readily appear from the foregoing, particularly from the description relative to Figures 13 and 16. Briefly, however, with the carriage in its lowermost position, after setting the machine for automatic operation .through closure of switch 285, the workpiece is loaded into the lower chuck during the period the light signal 258'is lit (sea K of Figure 13-). Thereafter, the. upper chuck head is elevated into engagement with the heat head and quenching fluid is supplied to the quench head (see E and G of Figure 13). Gradual 2,5 downward movement commences together with L. 01' Figure 13), so that the workplace is progressively heated and quenched thro ghout the 30 rested .for the dwell while the power is cut of! and v quenching and rotation continues. Thereafter rotation stops, the quenching head retracts and the carriage rapidly returns to its lowermost po-.

sition, at which point the upper chuck fixture elevates to provide access for removal of the workpiece.

As heretofore pointed out a number of safeguards appear throughout the apparatus and its organization whereby failure of various parts thereof or failure 01' certain predetermined op,- erating conditions acts to prevent injury to the apparatus. e

, Various features oi the invention, although but briefly described herein, are disclosed and claimed in copending applications as follows:

Serial No. 336,129, filed May 20, 1940, and relat ing to the heating head and its cooperation with the quenching head; Serial No. 419,828, filed November 21, 1941, and relating to the quenching "hfifl i Serial Nos.444, 346 and 507,817, filed May 25, ,1942, and October 2'1, 1943, respectively, and relating to the mechanism for actuating the quenching head; Serial No. 444,347, filed May 25,

1942, and relating to the work supporting carriage; and Serial No. 450,034, filed July '1, 1942,

and relating to the sequence controller.

Though only one embodiment of the invention has been illustrated and described, it is to be m understood that the invention is not limited thereto but may be embodied in various forms.' For example, workpiece holders, heads etc., may be varied to hold and operate. upon various types of workpieces and the operation of switches and 05 mechanism may be varied to suit requirements as desired. As such changes in construction and arrangement of parts may be made withoutdeparting from the spirit of the invention as will be apprrent to those skilled in the'art, reference will be hadto the appended claims for 'a deflnitionof the limits of the invention.

What is claimed is:

1. In an induction heat treating apparatus, a

frame a heat treating coil supported from one 7:; end or said frame, a quenching device supported 7 the apparatus should lowers to engage the upper end of the workpiece actuation of the switching transformer and de-' livery of power to the heat head coil (see I, J and v desired length at which time movement is arfrom the other end, work holding means mounted 1 on said frame, means for moving said quenching device into and out of operative relation with said coil, means for moving said work holding means coil and associated with said energizing means for controlling the energizing of said coil.

2. In a high frequency heat treating apparatus, a heat treating coil having fluid cooling means associated therewith, a quenching device adapted to be moved into and out of operative relation to said coil, means interrelated to said quenching device and coil and their normal operative position with respect to one another for controlling the flow of fluid in said cooling means, and means dependent upon the flow of fluid in said cooling means for controlling the supply of current to said c011.

3. In an inductionheat treating apparatus, an inducing head, a movable quenching head, means for relatively moving said heads into and out of operative relation with respect to each other, a movable work holding means having a movable work clamp thereon, means for moving said work holding means to place a workpiece clamped thereon in heating and quenching relation with said heads, means to energize said inducing head, a first control means associated with said energizing means and responsive to the positioning said quenching head in operative relation with said inducing head for controlling the energizing of said head, and a. sec'ond control means associated with said energizing means and with said moving means for'said work holding means and being responsive to the movement of said work clamp for controlling the energizing of said heating head and the movement of said moving means, said first control means being ineflective to control the energizing of said heating head independently of said second control means. I

4. In a heat treating apparatus having an electromagnetic inducing head; a quenching head; a work holder; means for effecting relative movement between said heads and work holder and an electrically operatable control device therefor;-

\ 7 piece to be heat treated in said work holder: control means therefor comprising a source of electric current, an operating circuit connected with said source and including said control devices and switch means for making and breaking the connections between said source and operating circuit, electrically operatable means for closing and opening said switch means, a conditioning circuit connected with said source and including said electrically operatable means and having starting contacts and a normally open switch therein said normally open switch being actuatable to closed position solely upon movement oi. said clamping device to said predetermined osition ,Yl by upon closure of said starting contacts energfz'ation of said electrically operatable means to connect said operating circuit with said source is dependent upon said clamping device being in its said predetermined position.

5. In a heat treating apparatus having an electromagnetic inducing head; a quenchinghead; a work holder; means for effecting relative movement between said heads and work holder and an electrically operatable control device therefor; means for supplying electrical energy to said inducing head and an electrically operatable control device therefor; means for supplying quenching medium to said quenching head and an electrically operatable control device therefor; and aclamping device carried by said work holder and means for moving said clamping device to a predetermined position to properly locate a workpiece to be. heat treated in said work holder; control means therefor comprising a source of electric current, an operating circuit connected with said source and including said control devices and switch means for making and breaking the connections between said source and operating circuit, electrically operatable means for closing and opening said switch means, a conditioning circuit connected with said source and including said electrically operatable means and having starting contacts and a normally open switch therein, said normally open switch being actuatable to closed position solely upon movement of said clamping device to said predetermined position whereby upon closure of said starting contacts energization of said electrically operatable means to connect said operating circuit with said source is dependent upon: said clamping device being in its said predetermined position, said clamping device moving means having an electrically operatable control device in said conditioning circuit in parallel with, said starting contacts and normally open switch.

I 6, In a heat treating apparatus having a quenching head, an electromagnetic inducing head provided with means for supplying electric energy thereto, an electrically operatable switch means for controlling said supply of energy and a cooling passage therein for cooling mud, and means for relatively moving said heads into and out of operative relation; control means comprising a source of electric current, a control circuit connected with said source and including a switch and said electrically operatable switch means for energizing and deenerglzing said switch means, means responsive to a change in the flow of cool ing fluid through said passageway for actuating said switch, and means responsive to the positioning of said heads in operative relation to change the flow of cooling fluid through said passageway whereby said flow responsive means actuates said switch. I

7. In -a heat treating apparatus having a summing head. an electromagnetic inducing head provided with means for supplying electric energy thereto, an electrically operatable switch means for controlling said supply of'energy and a cooling passage there n for cooling fluid, and means for relatively moving said heads into and out of operative relation; control means comprising a source of electric current, a control circuit sageway whereby said flow responsive means actuates said switch, said'positioning responsive means comprising a normally closed valve in said l7 s a passageway and arranged to be opened by said quenching head in said position of operative relation;

8. In an induction heat-treating apparatus, an

inductor, a quenching head, said inductor and head being relatively axially movable into and out of an adjacent heat-treating position, means for efiecting said relative movement, means for energizing said head, and control means associated said inductor in the absence of said adjacent heat-treating position.

' 9. In an induction heat-treating apparatus, an-

inductor having a cooling fluid passage associated therewith, a quenching head,'said inductor and quenching head being relatively movable into and out of a position of adjacent relationship,

means for efiecting said relative movement, means for supplying electrical energy to said inductor to energize the same, means for supplying a 18 cooling fluid to said passage, control mechanism associated with said passage and quenching head and responsive to movement of said inductor and quenching head to said position of adjacent re=- lationship to permit predetermined flow of cooling fluid through said passage, and means responsive to said flow of cooling fluid and associated with saidenergy supplying means to preclude energization or said inductor in the absence of said predetermined flow of cooling fluid.

10. The combination with an electromagnetic inducing head having a cooling passage therein, and a quench head, which said heads are relatively movable into and out of a predetermined position of adjacent relationship, of means operative in said position of adjacent relationship for establishing a. flow of coolant through said passage, an energizing circuit for said inducing head, means for opening and closing said circuit,

and means effective at a predetermined rate of coolant flow through said passage to cause said opening and closing means to close said circuit and eflective at a rate of coolant flow less than said predetermined rate. to open said circuit.

.nowARp E. SOMES. 

